Abstract
Echinococcosis is a parasitic disease caused by infection with tiny tapeworms of the genus Echinococcus. Heavy metals tend to bioaccumulate in living organisms, such as cow and sheep and their accumulation has been a major concern particularly in the tissues of these consumed domestic animals. Biological or Environmental monitoring of heavy metals is an interesting and important fast growing area that compose of utilizing a number of parasitic organisms as environmental bioindicators. The study aimed at assessing the possible undesirable effects of the excessive concentration of heavy metals in these consumed animals on the public health. In addition to clarifying the possible protective role of these parasites in protecting their hosts from serious danger through intake the heavy metals by these parasites rather than the tissues of their hosts particularly liver and lungs. A total of 116 liver and lung samples (89 of Liver and 27 of lungs) were collected from the slaughters of Erbil and Koya cities. A total of (84) parasites samples in two forms; Hydatid fluid (HF) and germinal layer (GL) were extracted and purified. Quantification of the heavy metals [Aluminum (Al), Arsenic (As), Cadmium (Cd), Mercury (Hg) and lead (Pb)] was carried out using inductively coupled plasma (ICP) technique. The results revealed different concentrations of heavy metals in different parasitized animals' organs (liver and lungs) with Echinococcus granulous parasite. As related with Arsenic (As) metal, it was detected in high concertation in parasitized bovine liver and sheep lungs tissues, which were almost two times higher in the parasite (HF) than the infected liver tissues and almost three times higher than healthy uninfected animals, P ≤ 0.05; and were one and half times higher in the parasite (GL) than healthy uninfected sheep animals, P ≤
0.05., while the slightly higher significant accumulation of mercury (Hg) was detected in these parasitized animals (GL), P ≤ 0.05. Lead (Pb) was also detected in highly significant concentration in parasitized bovine lungs (Hydatid fluid) which was three times, and two times higher than the infected tissues and healthy uninfected control, P ≤ 0.05. While, very low concentrations of Aluminum (Al) and cadmium (Cd) in the parasite, in opposite to infected animal tissues and healthy uninfected animals, by recording highly significant levels, P ≤ 0.001.
Whereas in a comparison between parasitized bovine and sheep's liver and lungs, Aluminum (Al) concentration was higher 7 times in parasitized sheep lungs compared with parasitized bovine lungs, P ≤ 0.05. While the same significant concentration was detected for both of cadmium (Cd) and Lead (Pb) in these animals. Mercury (Hg) was significantly higher in sheep liver than bovine liver, P ≤ 0.05. The same levels of Cadmium (Cd) were detected in both parasitized bovine's liver and lungs, P ≤ 0.001, and similar lead (Pb) level was detected in sheep's liver and lungs P ≤ 0.05. In conclusion, these significant results indicate the possibility of the role of Echinococcus parasite as environmental bioindicators and monitor of some heavy metals.
Keywords- Echinococcus granulous, hydatid fluid, germinal layer, heavy metals, Erbil, Koya, ICP